What are truncation errors?

Truncation errors happen when you cut something short and it doesn’t quite fit anymore.

Imagine you're trying to measure a piece of string with only your fingers, no ruler, no tape. You might say the string is about three finger-widths long. But if your finger is a little shorter than the actual length of the string, that’s a truncation error, it's like when you round up or down and lose some accuracy.

Like When You Round Numbers

Let’s say you're counting cookies in a jar. If there are 23 cookies and you just say "about 20," that’s a kind of truncation error. You’re making the number simpler, but it's not exactly right anymore. It’s like saying “I’m about five years old” when you’re really six, close, but not perfect.

Why We Do This

Sometimes we do this on purpose because it makes things easier to work with. Like how you might say "about 10 minutes" instead of counting every single second. It’s a trade-off: simpler math, but a little less exact.

So truncation errors are like when we make something shorter or rounder, not bad, just a bit less precise.

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Examples

  1. Rounding off a long decimal number like 3.14159 to just 3.14 is an example of a truncation error.

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